According to scientists, which atmospheric gas(es) made it possible for life to evolve on Earth?
it could be more than one.
a. water
b. carbon dioxide
c. nitrogen
d. ozone
e. oxygen
2007-01-18 08:54:30 · 3 answers · asked by JoAnna 2 in Science & Mathematics ➔ Biology
Water, but it was probably more important for that to be on the ground in liquid form.
The atmosphere may have been a "reducing" atmosphere of methane and ammonia. There was no free oxygen at the time.
2007-01-18 08:59:23 · answer #1 · answered by Anonymous · 0⤊ 0⤋
A: If there was no water vapor to turn into rain, then nothing could grow on land
B: Carbon dioxide was present in great quantities and was converted into Oxygen by early photosynthetic plants
C. Nitrogen gas is inert and does not take part in chemical reactions
d: ozone is very unhealthy for carbon base life forms.. death to the bacteria, used as a disinfectant.
e: oxygen is required for animals since they can't make their own oxygen.
Ozone is a definite No.
Nitrogen is a maybe. If the oxygen concentration was to great, more material would spontaneously combust and if the CO2 content was too high, then it would poison the animal life. Nitrogen does have a way of diluting the gases so that hazardous concentrations are not reached but it does not take place in the reactions.
Carbon dioxide was needed for the early life forms, for photo synthesis, but it was not until oxygen was present that the animal life could develop.
2007-01-18 17:06:24 · answer #2 · answered by Mr Cellophane 6 · 0⤊ 0⤋
its oxygen -- i am sure -- its the one thing besides water we need to survive
because water isnt a gas, and carbon dioxide and nitrogen (and ozone: not so sure about ozone) exsisit on other planets too but oxygen doesnt
2007-01-18 17:04:17 · answer #3 · answered by Sarah 2 · 0⤊ 0⤋